Find the section Energy cable insulation, jacketing and SZ lines and click on EEL 20 – 70 (pdf) and scroll down to look at the extrusion line drawings.

First note that the EEL 20 Insulation line and the EEL 30 Automotive Insulation line use dual cone flyer pay-off units for continuous operation but I worry about using a bunched strand on dual cone flyer pay-off equipment. Perhaps this can be achieved if tightening the bunch by flying with the direction of lay on the conductor. You would have to talk with the machine manufacturers and see if they will guarantee such a process for your conductor sizes.

Now look at the EEL 40 Insulation line and in your mind put smaller driven pay-offs as perhaps needed for your operation. Do you see the pay-off accumulator above the extrusion line? That is the device to allow you time to make the weld. You would also need a special welder from Strecker to make the weld inside a ceramic tube so that the dimensions of the conductor are maintained. www.strecker-limburg.de/index_en.php After the weld is made, the ceramic tube is broken off with a small hammer.

The weld must also be found on the take up reel and cut out of the product so very accurate length measurement is needed. Likewise you may wish to sense the weld at the crosshead and mark its position with and ink spray on the hot, just extruded plastic.

You may also require a take-up accumulator and/ or dual take-ups to keep the line operating continuously.

There are many companies that can make the extruder modifications but make sure that you deal with very technically qualified companies with really good reputations. Witness one of their lines in operation somewhere in the world long before you purchase anything. Make sure you have some frank discussions with the wire company that owns and operates the equipment without the machine manufacturer nearby so that you can get clear and frank information about operating and maintenance problems etc.

In our company we are using dual cone pay-off. These pay-offs have openings on the sides. Just make sure that during the bunching process, the starting conductor is outside the drum. If you will do this, it will be easier for you to weld even though the extrusion is running.